Film-developing machine having positive drive



Jan. 3, 1928.

V. C.-'DE YBARRONDO FILM DEVELOPING MACHINE HAYING POSITIVE DRIVE Filed Aug. 9, 1926 l mrc'i/vr C. DE X61419, ONOa,

HTTOZPNEK .85 When the tension of the film Patented Jan. 3, 1928.

VINCENT'G. DE YBABRONDO, OF LOS ANGEiIES CALIFORNIA.

.mu-nnvnnorme macniim navmo POSITIVE mam.

Application fled August 9, 1928. Serial No. 128,038.

This invention-relates to the art of developing photographic film, and. it is embodied in an automatic film develo 'pecially suited for developing motion picpositive and nega- 6 two film. In this art both tive film, after their exposure, are subjected to a series of treatments which prepare them for the cutting room.

enerally passes through the following steps.

10 e film is first developed by immersion in a developing solution; the images are fixed thereon by immersion of the film in a fixative solution; the film is'then cleansed of all the adhering solutions by immersion in a wash;

the film may then be dyed and toned as desired; and the film is then dried. The film thus treated is ready for the cutting room.

Motion picture this series of treatments either manually or by automatic apparatus and my invention relates to an automatic apparatus. for carrying a motion picture film through the series of treatments enumerated above. In such machines the film is passed through the various solution tanks or wet box and the drying compartments or dry box. The wet box and the dry box have series of upper and lower spools or rollers on which the film'is wound. In the usual film developing machine the drive rollers thereof are driven through a friction means, such as'a friction clutch, from a drive shaft which operates at a constant rate of speed. The lower rollers are rotatably disposed on a fixed shaft. passing through such a machine is greater than normal tension, the friction will slip until the film is returned to normal tension. It is evident that the maintaining of the film at a uni- 40 form and normal tension is somewhat precarious since the operation of such a friction clutch is not altogether certain.

. I have discovered that the tension of the maybe accurately controlled by ositively drivin the upper rollers at a uni rate of spec and by floating thelower rollers; that is, arranging the lower rollers so i that they may move vertically and sothat 3 they are supported entirely by the film which 80 passes therearound.

Itis accordingly one of the objects of this invention to provide a film developing apparatus in which the upper rollers are positively driven at a substantially uniform rate A of speed and in which the lower rollers are ping machine es- The exposed film ms are carried through Form full-floating and are supported entirely by the film.

The film developing apparatus is generally divided into a number of units, each of which is operated by a separate drive means;

The wet box may be divided into aseries of units and the dry box may also be divided into a series of units, each of the different units having a separate drive means. It

often occurs that the different units will not be operated at the same rate of speed and one of t em will operate faster or slower than the other ofthe units, this causing either a' slack or a tensionin the film which is detrimental to the film.

It is an object of this inventionto rovide a film developing apparatus in whlch the operation of one of the units is controlled so that it will operate in congruency with the other of the units.

In order to accomplish the last named object of the invention it has been necessary to devise a special form of rheostat operated entirely by the film passing through the developing apparatus.-

It is another object of my invention to provide a novel film operated rheostat.

Other objects and advantages will be made manifest hereinafter.

Referring to the drawings, which are solely for thepurpose of illustration and in which I illustrate a preferred form of the invention:

Fig. 1 is an elevationalview tioned of the invention.

Fig. 2 is a fragmentary p on the line 22 of Fig. 1.

Fig. 3 is a section taken on the line 3-3 of Fig. 1.

Fig. 4 is an enlarged fragmentary view'of 95 the novel rheostat of my invention. M

Referring in detail to the drawings, particularly F1 1, the numeral11 represents rimary an secondary units which in the rawings are shown as identical and be ng part of the wet box of the film developing a paratus. It should be clearly understood tlEat these units 11 may be dissimilar andpne or both-may be a part of the dry box. Since each of the units as shown are identical, only the left-hand or primary unit will be described in detail; 4 Referring to this unit, 12 represents a tank in which a suitable solutionor solutions may I partially sec- 9o lan view taken 'be placed. Supported at the upperrpart of 11 the tank 12 is. ,a frame 13 having side bars 14 and end bars 15. Extending across the frame 13 and rotatablysupported by the side bars 14 are drive shafts 16. Rigidly secured to the'drive shafts 16 are upper drive rollers 17 around which a film 18, which is being treated, is passed. Rigidly secured on the outer ends of the drive shafts 16"are. drive gears 19, between which are intermediate gears 20. The intermediate gears, 20 are rotatably supported by brackets 21 and are in mesh with adjacent drive gears 19. The drive gears and intermediate gears 19 and 20 are driven by means of a motor 22 having a gear 23 which engages and operates one of the drive gears 19, the other gears being driven therefrom. The motor 22 is connected in an electric circuit 24. A control device 25 is provided for controlling the supply of current to the motor 22 of the primary unit.

Extending downward into the tank 12 from the sidebars 14 of the frame 13 are vertical legs 28. The vertical legs 28 are pro- -vided with vertical slots 30. Extending between the bars of vertical legs 28 are floating shafts 31 having heads 32 which rest in the 'vertical slots 30. The floating shafts 32 are free to move vertically in the slots but are restrained from horizontal or lateral movement. Supported on the floating shafts 31 are full floating lower rollers 33. The film passes around the-under sides of the floating rollers 33 and supports them as illustrated in Fig. 1.

The film, in passing from theleft-hand or primary unit 11 to the right-hand or secondary unit, passes over a roller 35 and over a second roller 36, there being a loop 37 Supported at the lower end of the loop 37 is a pulley 38 which 'is attached by a connect-ion 39 to the outer end of an arm 40. The arm 40 is extended from a contact drum 41 of the automatic rheostat of my invention. The contact drum 41 is pivotally supported on a shaft 42, which shaft 42 is in turn carried by a frame '43. 'The'rheostat contact drum 41 is pro-- vided with a series of contacts 44 which are consecutively connected together by resistance wires 45. One of the end contacts 44 is connected to a wire 46 which forms a part of the circuit. 24. The automatic rheostat of the invention also includes a contact finger 47 which is adapted to engage one of the contacts 44 according to the position of the drum 41. The contactfinger 47 is connected to a wire 49 which forms a part of the circuit 24 and which is connected to one of the terminals of the motor 22 which operates the right-hand unit 11.

The control device or rheostat '25, which operates the left-hand unit 11, is manually operated and may be set so that the left-hand unit will operate at any desired rate of speed. The right-handunit 11 is controlled in speed by the automatic rheostat which is actuated by the loop 37 of the film 18.

The complete operation of the invention Is as follows:

The film is first wound around the drive and floating rollers 17 and 33, as illustrated in the drawings. The floating rollers 33 are full floating and are entirelyv supported by the loops of the film'18. After the film (or a leader) has been wound as shown in Fig. 1, the circuit 24 may be completed and both of the motors 22 set into operation. drive rollers 17 are each driven positively and at a uniform rate of speed. The weight of the floating rollers 33 maintains the tension of' the film uniformly at a normal tension. In case of any variations in the lengths of the loops which support the floating rollers 33, the floating rollers may move up or down, this being permitted by the heads of the floating shafts 31 which may move up or down in the slots 30. I I

In the event that the first innit operates at a faster rate of speed than the secondunit or that the film stretches, the loop 37 which supports the pulley 38 will lengthen and the contact drum 41 will rotate in a. direction indicated by the arrow 50 of Figs. 1 and 4. If necessary, a. weight (Fig. 1) may be attached to the arm 40. When the contact drum 41 is rotated, a different contactt44 is moved into engagement with the contact finger 47, and some resistance is cut out of that The Y portion of the circuit 24, which is connected to the secondary motor 22, which operates the secondary or right-hand unit 11. "Therefore, the motor of the right-hand unit will be accelerated in speed and the loop 37 will be.

slowed up, this resulting in the lengthening of the loop 37.

It is often necessary to speed u or' slow down the operation of the film evelopin'g apparatus according to the exposure of the film. This may be accomplished in .thejnvention by operating the rheostat 25. This speeds up the operatlon of the left-hand unit 11, and the automatic rheostat of the inven-- tion will automatically speed up the operation of the right-hand unit 11, in agreement with the left-hand unit 11. I

The invention, as fullydisclosed, is of simplified construction and positive in operation. The tension of the film will be maintained at normal and re uires no adjustment and will give no troub e. One of the important parts of the invention, as has been emphasized heretofore, is the positive driving of the drive roller 17 and the full floatmlg feature of the floating rollers 33. Anot er important feature of the invention is the controlling. of one of the units so that said film being also handled by said second-' ary unit; a primary motor for operating said drive rollers of said primary unit; a secondary drive motor for operating the drive rollers of said secondary unit; a contact drum connected in a circuit to said secondary motor, said contact drum having a plurality of contacts in series; a pulley attached to said contact drum, said film supporting said pulley andthus determining the position of sa1d contact-drum; and a contact finger connected in the circuitof said secondary motor, said contact finger engaging one of said contacts according to the position of said contact drum, said contact drum and said contact finger supplying current to said secondary motor so that said secondary unit will operate in congruency with said primary unit;

2. A film developing apparatus comprising: a primar unit having drive rollers,

there being :1 kn handled by said primary unit; a secondary unit having drive rollers, said film being also handled by said secondary unit," a firimar motor for operating sa1d drive ro ers 0 said primary unit; a secondar drive motor for operating the drive r0 lers of said secondary unit; means for controlling the supply of current to said primary motor; a contact drum connected m a circuit to said secondary motor, said contact drum having a plurality of contacts pointed out, in the lm handled by said primary in series; a $3318} attached to said contact drum, said supporting said pulley and thus determining the position of said contact drum; and a contact finger connected in the circuit of said secondary motor, said contact finger engaging one of said contacts according to the position of said contact drum, said contact drum and said contact finger supplying current to said secondary motor so that said secondary unit will oper ate in congruency with said primary unit.

3. A film developing apparatus comprising: a frame; a plurality of drive shafts journalled in spaced relation on said frame so as to be substantially parallel and on the same level; drive rollers, one of which is rigidly fixed upon each of said shafts; means for driving said shafts positively and in synchronism; substantially vertical struts provided on said frame, a pair of said struts eing disposed under the s ace between each adjacent pair of shafts, t e struts of each of said pairs being provided with co-operating, substantially vertical uideways; travelling shafts, each of which has end formations adapted to slide Within said guideways of one of said pairs of struts; travelling pulleys, one of which is rotatably mounte upon each of said travelling shafts; and a leader ribbon which is adapted to be threaded through said apparatus so as to alternately pass over the top'of one of said drive ulle s and under the next succeeding one of sai travelling pulleys so as to support said travelling pulleys so that any stretch or shrinkage in any portion of a film drawn into said apparatus by said leader ribbon is compensated for by the fallin or rising of the travelling pulley supporte by said portion of film.

In tes timon whereof, I have hereunto set my hand at as Angeles, California, this 3rd day of August, 1926.

VINCENT 0. 1m rBARRoNno. 

